<!DOCTYPE html>
<html>
<head>
  <script src="https://cdn.rawgit.com/konvajs/konva/1.4.0/konva.min.js"></script>
  <meta charset="utf-8">
  <title>Konva Remove Event Listener Demo</title>
  <style>
    body {
      margin: 0;
      padding: 0;
      overflow: hidden;
      background-color: #F0F0F0;
    }
    #buttons {
        position: absolute;
        top: 5px;
        left: 10px;
    }
  </style>
</head>
<body>
  <div id="container"></div>
  <div id="buttons">
    <button id="removeClick">
      Remove onclick
    </button>
  </div>
  <script>
    function writeMessage(message) {
      text.setText(message);
      layer.draw();
    }

    var stage = new Konva.Stage({
      container: 'container',
      width: 300,
      height: 300
    });

    var layer = new Konva.Layer();

    var circle = new Konva.Circle({
      x: stage.getWidth() / 2,
      y: stage.getHeight() / 2 + 10,
      radius: 70,
      fill: 'red',
      stroke: 'black',
      strokeWidth: 4
    });

    circle.on('click', function() {
      alert('You clicked on the circle');
    });

    layer.add(circle);
    stage.add(layer);

    document.getElementById('removeClick').addEventListener('click', function() {
      circle.off('click');
      alert('onclick removed');
    }, false);
  </script>

</body>
</html>